Epilepsy and Seizures In Dogs and Cats

Epilepsy is the general term for a disorder of the neurological system (which involves the brain, spinal cord and/or nerves) that may cause an animal to have sudden, uncontrolled and often recurring seizures (fits), with or without loss of consciousness; they may also show abnormal behaviours such as air-snapping/fly-biting, excessive vocalisation, aggression without provocation, restlessness or fixed staring. In most cases epilepsy is a lifelong condition and an animal that has more than one seizure is expected to have more frequent or severe seizures in the future. Sometimes however, seizures can be temporary problem caused by illness or toxicity that is affecting the neurological system.

The seizure itself is caused by an ‘electrical storm’ in the brain. The brain has millions of nerve cells called neurones, which control the way animals (and humans) think, move and feel. The nerve cells pass electrical signals to each other and if these signals are disrupted, or if too many signals are sent at once, this causes a seizure, also known as a ‘fit’.

A Seizure or fit is a symptom of a disorder that is affecting the brain and is not a disease in itself. The cause may be

Genetic: This is most common in pedigree dogs and affected breeds include Beagles, Labradors, Golden Retrievers, Vizslas, Springer Spaniels, Border Collies and Poodles. It usually becomes apparent from 10 months to 5 years of age. It is thought to be less common in cats due to their genetic diversity.

Structural or Metabolic: The seizures can be caused by an underlying brain problem (e.g. anatomical malformation, a tumour or lesions, infection, inflammation and injury), a metabolic disease or problem ( diabetes, chemical imbalances etc.), toxins/poisons (e.g. permethrin, allergic reaction) or heatstroke for example.

Unknown (Idiopathic): The cause of the seizures has yet to be or cannot be found.

Types Of Seizure

The two most common types of seizure in dogs and cats are

Generalised seizures (Grand Mal): There will be collapse, loss of awareness, shaking of limbs, chewing and/or facial twitching, as well as salivation, urination and defecation.

Partial seizures (Petit Mal): These are more common in cats than dogs and, because they only affect part of the body, they can be more difficult to identify. Symptoms can include salivation, staring, facial twitching, eyelid twitching, rapid contraction and dilation of the pupils, vocalisation and aggression. Partial seizures sometimes turn into generalised seizures occurring several times during the day.

Stages Of A Seizure

In some animals these stages can be quite extreme, while others may show only a few, mild signs.
Seizures often occur while the pet is relaxed and resting quietly in the evening or overnight, or they can be triggered by particular events or stress.

Owners of pets with long-term epilepsy can sometimes predict when a seizure is coming based on their pet’s behaviour and often witness increased anxiety related behaviours (whining, clingy), a reluctance to perform normal activities and increased hiding behaviours. The prelude to an actual seizure can last from minutes to hours and animals tend to pace, lick, salivate and sometimes urinate or vomit.
During actual seizure (The Ictal Phase), which may last from a few seconds to a few minutes, you may see involuntary muscle tone and movement (twitching, spasms). The animal will often fall over, become stiff and/or paddle with all four limbs; it may also chomp its jaw, salivate, urinate, defecate and vocalize.
After the seizure (The Postictal Phase), the dog or cat may show signs such as disorientation, restlessness, pacing, increased thirst and appetite, weakness and sometimes temporary blindness. This phase can last minutes, hours or days in more extreme cases

Frequency Of Seizures

Self-Limiting: One seizure within a 24 hour or longer period

Clustered: Two or more seizures in a 24 hour period, lasting less than 5 minutes each, with the pet displaying normal behaviour in between the seizures

Status Epilepticus: Continuous seizures that last for 5 minutes or longer or without a return to normal behaviour between the seizures. Immediate veterinary treatment is necessary for these seizures because they can lead to permanent neurological damage or death

What To Do If Your Pet Has A Seizure

Seizures can be very alarming but try to stay calm, most are very quick, only lasting 30 – 60 seconds (although it may feel like much longer while you are watching).

1. Seizures can be made worse by stimulation such as touch, sound and light, so darken the room if possible and turn off the tv/radio.

2.Don’t touch your pet unless he is in immediate danger of injury. If your pet is in a relatively safe place, leave him alone. He won’t swallow his tongue so don’t try and pull it forward or you may end up getting bitten (or worse cause him to bite his own tongue). If your pet is in a place where he might injure himself you can place a buffer such as a rolled blanket or cushion between him and the object.

3. Owners of epileptic pets are encourage to keep ‘seizure diaries’ as they can be very useful for the vet in determining medication dosage, patterns ,triggers.

• Record the length of time of the seizure
• Note the time of day and if anything unusual happened, or if your dog was acting out of character.
• Note what happened before and during the seizure; pacing, salivating, collapse, jaw chomping, just twitching/spasming or paddling feet etc. (It can be useful to film the seizure to show to your vet if you have your mobile phone to hand)

4. Give your pet time to quietly recover from the seizure and then contact your veterinary practice to let them know about the seizure.

5. After the seizure itself (postictal phase) your pet may appear to be very disorientated. In some cases talking calmly and stroking can help, but do not try this if your pet appears to be irritable or agitated; they are still not in complete control of themselves and may scratch, snap and/or bite without realising what they are doing. The best advice is usually to make sure he or she cannot get injured and leave them alone to let them recover.

If the seizure lasts longer than 4 minutes, your pet is having repeated seizures, or your pet is showing twitches and/or tremors that are not settling after an hour or so contact your vet for advice.

Diagnosing Epilepsy

Unfortunately there is no one test available to give us a diagnosis of epilepsy, so your vet may need to perform several investigations in order to exclude other causes of the seizures such as metabolic disturbances (diabetes), toxins, cardiac and/or pulmonary disease and myasthenia gravis which all have symptoms that can mimic seizures.

The first thing will be to give the pet a thorough examination and get a detailed description from you about the seizure(s) including their frequency, duration, and severity, as well as any signs of abnormal behaviour before and after. Following this, tests may include

Blood and urine samples may be taken for analysis at the practice or by an external laboratory

X-rays, CT or MRI Scans may be performed to try to pinpoint the cause of the seizures

Cerebrospinal fluid may also be analysed by a laboratory as this can help identify problems such as Disease, infection, inflammatory conditions and cancers

Treatment And Management Of Epilepsy

There are several drugs available to treat epilepsy and the vet will decide which is best for your pet, based on the number, type and frequency of seizures he or she is having. Some epileptic pets may require more than one type of medication in order to control their seizures. Side effects can occur with treatment, but they are usually worse in the initial stages of treatment and the severity normally decreases over time. Common side effects can include lethargy, increased thirst and hunger (leading to increased urination and weight gain), panting, hyper excitability and restlessness.

While successful treatment will hopefully reduce the frequency of the seizures, intermittent seizures may still occur so owners need to be prepared for this to happen.

It is very important for the vet to monitor an epileptic pet closely, he or she may also need to test the therapeutic levels of drugs in the pet’s blood, so that the drug dosage can be adjusted if necessary. Initially the vet may recommend check-ups and tests every 2-4 weeks and then every 3-6 months.

Antiepileptic drugs should never be stopped suddenly as this may cause ‘withdrawal seizures’. If you have an epileptic pet, make sure that you always have enough medication at home for them.

Epileptic dogs have a tendency to become overweight because of the medication and increased hunger after a seizure, so care must be taken to ensure that they remain at their ideal bodyweight.

After a full health check by the vet, pets that have only had one isolated seizure (or have very infrequent seizures) may not need medical treatment and further investigation unless the frequency of seizures increases.

The good news is that the majority of epileptic pets have a good prognosis and can lead happy lives as long as the condition is controlled and they are monitored closely.